Effect of laser radiation parameters on the conductivity of structures produced on the polycrystalline diamond surface

Abstract The objective of this investigation is to study the effects of laser radiation at 532 nm, the second harmonic of Q-switched Nd:YAG laser on polycrystalline diamond in air and liquid (water and H2O2) ambient. Phase changes and laser-induced stress due to structural deformations are analyzed using Raman spectroscopy. Surface morphology of the processed region of diamond and formation of microcracks is studied by scanning electron microscopy. Drilling of diamond substrates, in water ambient, is observed to be faster, 1.364 times, than that in the air. Enhancement in the drilling speed and uniformity of the drilled hole are discussed from the view of presence of reactive hydrogen and / or oxygen radicals liberated during the interaction of laser radiation with the diamond surface in water ambient.

Download Full-text

Femtosecond Pulsed Laser-Induced Micromachining of Difficult-to-Machine Materials: Diamond a Case Study

10.1115/imece2000-1905 ◽

2000 ◽

Author(s):

A. P. Malshe ◽

A. M. Ozkan ◽

T. A. Railkar ◽

K. P. Adhi ◽

W. D. Brown ◽

...

Keyword(s):

Raman Spectroscopy ◽

Excimer Laser ◽

Etching Rate ◽

Polycrystalline Diamond ◽

Single Pulse ◽

Laser Wavelength ◽

Diamond Surface ◽

Single Shot ◽

Micro Machining ◽

3 Dimensional

Abstract Meso and micro scale machining is an important and emerging area of research. Various non-traditional and novel tools are being explored for meso and micro machining of non-silicon materials. In this paper, we report etching, micro machining and related phenomena of commercially available single and polycrystalline diamond using a femtosecond pulsed excimer laser (λ = 248 nm, tp ∼ 380 fs). Surface modifications due to single pulse and multiple pulse irradiation of diamond samples, at different energy densities, have been analyzed using Raman spectroscopy, scanning electron microscopy (SEM) and atomic force microscopy (AFM). Etching rate of single crystal type IIA diamond by femtosecond pulsed excimer laser is also studied. Raman spectroscopy study of the single shot irradiation of diamond with a femto second laser shows the formation of a non-diamond disordered (sp2 bonded) phase on the surface. However, subsequent micro machining of this non-diamond disordered surface, by delivering several shots from the femtosecond laser, results in the removal of the non-diamond disordered layer and the restoration of the diamond surface. It is experimentally shown that the periodicity of the 2-dimensional corrugations written on diamond surface is shorter than the laser wavelength used. 3-dimensional writing on diamond globules during laser etching is also discussed. Further, micro machining of diamond tips is shown to be precise, and without mechanical and chemical damages. Femto second laser is demonstrated as a next-generation tool for mechanical and chemical damage free precision micro machining of the hardest material, diamond.

Download Full-text

Fabrication of nano-needle arrays on diamond surface by reactive ion etching

MRS Proceedings ◽

10.1557/opl.2012.446 ◽

2012 ◽

Vol 1395 ◽

Author(s):

T. Misu ◽

K. Koh ◽

T. Arai

Keyword(s):

Stainless Steel ◽

Reactive Ion Etching ◽

Polycrystalline Diamond ◽

Diamond Surface ◽

Stainless Steel Electrode ◽

Sintered Ceramic ◽

Ion Etching ◽

Steel Electrode ◽

Diamond Substrate ◽

Substrate Surfaces

ABSTRACTCVD polycrystalline diamond surfaces were etched using reactive ion etching system with either a conventional stainless steel electrode or MgO sintered ceramic containing electrode. The micro-needle array of high aspect on diamond substrate surfaces obtained with MgO electrode was fabricated by using back-sputtering from MgO electrode. The RMS roughness of diamond substrate surfaces obtained with MgO electrode is higher than those obtained with stainless steel electrode.

Download Full-text

Growth of (100) oriented diamond grains by the application of lateral temperature gradients across silicon substrates

Journal of Materials Research ◽

10.1557/jmr.2004.0433 ◽

2004 ◽

Vol 19 (11) ◽

pp. 3206-3213 ◽

Cited By ~ 1

Author(s):

E. Titus ◽

D.S. Misra ◽

Manoj. K. Singh ◽

Pawan. K. Tyagi ◽

Abha Misra ◽

...

Keyword(s):

Substrate Surface ◽

Chemical Vapor ◽

Polycrystalline Diamond ◽

Film Deposition ◽

Temperature Gradients ◽

Diamond Surface ◽

Silicon Substrates ◽

Oriented Growth ◽

Oriented Samples ◽

Diamond Grain

Polycrystalline diamond films with a predominant (100) texture were deposited onto silicon substrates using hot-filament chemical vapor deposition. During film deposition, different temperature gradients were created and imposed laterally across the substrate materials. Films grown under a gradient of 100 °C cm−1 displayed large (100) oriented grains. No crystallite (100) orientation was observed in the as-grown films prepared without a temperature gradient. It was observed that the diamond grain size varied as a function of the gradient. The lower gradient resulted in smaller grains and vice versa. Furthermore, the size of the grains was a function of the deposition time. The orientation of the diamond grains changed gradually across the substrate from (100) to (110) orientation as we scanned from the high-temperature to the low-temperature zone. The films were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier transform infrared (FTIR) spectroscopy. XRD showed strong (400) reflections in the oriented samples. SEM results indicated the presence of smooth diamond surfaces consisting of predominantly (100) oriented platelets. As the (100) oriented diamond grains were grown on top of the (100) oriented silicon substrates, the faces were mostly aligned parallel to the substrate surface resulting in the deposition of a smooth diamond surface. AFM observations revealed the presence of steps located at the boundaries of the oriented grains. FTIR results showed the characteristic difference in hydrogen bonding in the oriented samples and gave useful information about mechanisms responsible for the orientation. Quantitative analysis was carried out to measure the H content in the films, and it was found that the oriented films contained less hydrogen. Our findings suggest that high saturation of carbon and a concentration gradient of sp3 CH2 species can be the key factor in the oriented growth of (100) diamond grains.

Download Full-text

The Interaction of Carbon with the Diamond Surface: A Photoelectron Spectroscopy Study

MRS Proceedings ◽

10.1557/proc-498-77 ◽

1997 ◽

Vol 498 ◽

Author(s):

P. Reinke ◽

T. Wrase ◽

K. Müller ◽

P. Oelhafen ◽

R. Locher

Keyword(s):

Photoelectron Spectroscopy ◽

Carbon Film ◽

Polycrystalline Diamond ◽

Carbon Films ◽

Electron Beam Evaporation ◽

Diamond Surface ◽

Field Emission Current ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Reconstructed Surface

ABSTRACTThe modification of the diamond surface through adsorbants offers the opportunity to adjust the electronic and electron emission properties of the surface. In the study presented here, we deposited between 0.1 and 100 monolayers of carbon from an electron beam evaporation source on polycrystalline diamond films. Photoelectron spectroscopy in the ultraviolet and X-ray regime was employed to characterize the surface. Observations on a (100) polycrystalline diamond film show, that the surface is first depleted of hydrogen and subsequent growth of an amorphous carbon film (a-C) occurs on the reconstructed surface. The deposition of these ultrathin carbon films allows the controlled introduction of sp2carbon and p-π states onto the diamond surface. The field emission current increases considerably with the amount of sp2-carbon accumulated at the diamond surface. The current-voltage characteristics only partially follow the Fowler-Nordheim equation, and the results obtained for different films are described and possible emission mechanism discussed.

Download Full-text

Giant Reflection Coefficient on Sc 0.26 Al 0.74 N Polycrystalline Diamond Surface Acoustic Wave Resonators

physica status solidi (a) ◽

10.1002/pssa.201900360 ◽

2019 ◽

Vol 216 (20) ◽

pp. 1900360

Author(s):

Miguel Sinusía Lozano ◽

Zhuohui Chen ◽

Oliver A. Williams ◽

Gonzalo F. Iriarte

Keyword(s):

Reflection Coefficient ◽

Acoustic Wave ◽

Surface Acoustic Wave ◽

Polycrystalline Diamond ◽

Diamond Surface ◽

Acoustic Wave Resonators

Download Full-text

Atomic layer deposition of high-κ layers on polycrystalline diamond for MOS devices: a review

Journal of Materials Chemistry C ◽

10.1039/d0tc02063j ◽

2020 ◽

Vol 8 (38) ◽

pp. 13127-13153

Author(s):

Aneeta Jaggernauth ◽

Joana C. Mendes ◽

Rui F. Silva

Keyword(s):

Atomic Layer Deposition ◽

High Performance ◽

Polycrystalline Diamond ◽

Atomic Layer ◽

Diamond Surface ◽

Mos Devices ◽

Layer Deposition

Working in concert, diamond layers and high-κ films impart opportunities for high performance MOS devices. Optimization hinges on their interfacial quality inciting investigation into diamond surface terminations and ALD parameters to ensure success.

Download Full-text